I have it set to do a image full backup every day (and have done this for years) Usual time for this was approx 16 minutes. Never had a problem, and have lost count of the times it has got me back on the road in times of trouble.
Now, suddenly it is taking 4-5 hours to get near the end of this task.....
My C:\ drive shows 728Gb free of 930GB - therefore image equates to approx 200Gb
this is being backed up to an internal drive....
16 minutes is remarkably fast for imaging 200GB. Your specs say your cpu is a 2nd gen. i3, but even my fastest machine with a 6th gen. i7 and an SSD for its C: drive takes nearly an hour to make a Full image of slightly less than 200GB from the source drive, according to its logs.
Imaging Summary
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Total Selected: 181.97 GB
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Destination:
Backup Type: Full
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I/O Performance: Read 1.7 Gb/s - Write 1.2 Gb/s
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Image and Verification Completed Successfully in 00:50:05
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Your 16 minutes to completion is more typical of a Differential or Incremental image. Are you sure you were previously doing a Full image? You can check that in Macrium's logs for your previous images. Here's that same machine of mine performing an Incremental.
Imaging Summary
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Total Selected: 210.13 GB
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Destination:
Backup Type: Incremental
...
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I/O Performance: Read 1.5 Gb/s - Write 1.5 Gb/s
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Image and Verification Completed Successfully in 00:15:16
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